1. Field of the Invention
The invention relates in general to the field of in-pipeline fluid-cooled electronic circuit devices, especially fluid-cooled computer system components.
2. Description of Related Art
Current server, datacenter and High Performance Computing (or HPC) subsystems are composed of tens to hundreds of densely packed blades, assembled per chassis, rack and point of delivery (PoD, i.e., a container-sized server cluster). Packaging density and PoD sizes are increasing the stress on the input/output (IO) scalability, whether electrical or optical.
Recent multicore CPUs (central processing units), faster higher density memory and IO busses, virtualization, multiple gigabit Ethernet interfaces integrated on-chip all have exposed the gap between the increasing communication demands and the limited pin IO capabilities of packaging. For instance, chip multiprocessors (CMPs) attempt to maximize the performance and more efficiently use the increasing silicon area, also benefiting from new 3D stacking packages. However, their achievable memory-level parallelism (MLP) is IO-limited for online transaction processing (OLTP), business analytics, Partition-Aggregate, Hadoop etc., datacenter workloads, as well as for HPC and media/streaming applications that are bandwidth-bound. Lacking sufficient IO bandwidth, CMPs must often settle for a fraction of their achievable MLP, which increases the practical difference between peak and sustained performance, typically a fraction of the former.
More generally, recent evolutions in the IO pin density has led to substantially increased wiring/interconnect densities. The increased density has raised new thermal engineering challenges, addressed by liquid, instead of the current air cooling that is both insufficient for the upcoming energy densities, and inefficient with respect to datacenter PUE factors. Recent announcements indicates that at least some of the next generation's large systems will be liquid-cooled, using water, oil and/or other convenient thermal agents, e.g., by external dunking of boards, blades, chassis, racks in appropriately sized vats filled with clear oil, circulated by large pumps, as proposed by Intel.